drewp

Cheap usb rfid reader

Posted in hardware, rfid, rpi by Drew Perttula at 2019-04-07T11:29:47.873309-07:00

This PN532 board has better read range than my first try, which was this RC-522 board. But, the PN532 possibly uses I2C clock stretching, which makes it fail sometimes on my Raspberry Pi 3B+. The flakiness sometimes takes hours to show up, and I couldn't find a software way to reset it short of a reboot.

What seems to work better is to make it a USB board with a CP2102 usb serial chip. Now I have [raspberry pi 3B+] -> [usb serial] -> [PN532 in UART mode]. The libnfc path for it is LIBNFC_DEFAULT_DEVICE=pn532_uart:/dev/ttyUSB0.

Here's how to connect the boards right against each other:

drewp - April 11
https://planb.nicecupoftea.org/2019/03/27/an-i2c-heat-sensor-with-a-raspberry-pi-camera/ talks about doing software i2c on some gpio pins, which might have helped.
New comment

Your name:

Your email address (won't be redisplayed):

Comment: </div> <div> <input type="submit" class="postButton" value="Post comment"/></div> </form> </li> </ol>  </div>  (prev/next buttons not implemented; use search) </div>    <hr/> </div> </div> </div> </div> </div> <div id="footer"> <p>The Green Marinée template by <a href="http://e-lusion.com" title="Ian Main - e-lusion.com">Ian Main</a> - Built for Wordpress 1.5, ported to this custom site by Drew</p> <div class="extras"> <ul>  <li><a href="/atom" title="Subscribe to Atom feed">Atom</a></li> </ul> </div> </div> </div> </body> </html>

drewp

Recent Posts

Search

Categories

Cheap usb rfid reader